Today I finally managed to have a look at the Uno Eagle files. The first thing that strikes is that it does not offer a possibility to resolder the headers with proper alignment. There would have been enough space left on the board for this option. Since the issue of the misaligned headers is well known this is again a lost opportunity to fix this. Obviously the Arduino team does not intend to fix this at any time in the near future. This is something I definitely do not like.

Then I figured that this board has basically two full blown controllers. Both with dedicated ISP headers. Cool. But for whatever reasons the 8U2 has a whole bunch of unconnected pins. Some breakout solder pads would have been nice. Why was this ommited?

One thing that I do not get at all is the the crystal oscillators. What good for are the 1M resistors between the caps?

jezuz

Just a comment about the headers. It's a branding thing - it's part of what the arduino is. Clone boards based off of different micros have even followed with the same awkward layout. It's just a matter of preserving tradition, so I guess you'll just have to deal with it.

Not exactly my point. As I understand it the weird header spacing is an "accident". Of course I would think it is branding but the claim is that it is not. If so, then I would expect the option to resolder the headers to make it fit standard spacing. Thus it would become possible to resolder the headers accordingly or to add a second row of standard spaced headers.

The odd spacing was a 'brain fart' caused by the rush to meet some deadline on the first issue Arduino boards. The early shields were made to fit the error and then it couldn't be changed without causing problems with the shields. Nothing to stop them putting a second row inside the 'official' one at the correct spacing however. Would make stripboad shields an awful lot easier.......

It would still be possible to get rid of the de facto standard. Of course any new board has to be compatible to old shields.

The solution is to just provide the second row. For manufactured shields the weird spacing is no issue. Anyone who wants to do a homebrew shield on stripboard is most probably capable to handle a soldering iron. So if the second row would be in place it would be pretty simple to resolder as needed.

It would be even possible to switch by offering boards with both rows for 3 years and bring out a roadmap that tells that in 3 years from now the new spacing will be the official one.

admin

Obviously the Arduino team does not intend to fix this at any time in the near future. This is something I definitely do not like.

where did you read this? We definitely want to fix it at some point but the current layout works for a lot of people and there are other issues we want to take care of.

Some decision in the arduino project are take without following "standard engineering practice" for example I always found the double row of pins to be very very ugly and it confuses beginners.

The same goes for the atmega8u2 in our mind that is a replacement of the FTDI chip that can do more and it's more open source. two very important goals for us. Connecting the other pins to some pads or connector would have made the board incredibly more complex while we worked hard to gain more "empty space" on it.

Again this to make the board less intimidating.

Current "professional" development systems for microcontrollers have gazillions of pins, connectors, switches, ports, buttons, LEDs and more just because they might be useful one day. this logic works well in the engineering world but in a world of people who see their first microcontroller of their life "less is more" works well.

There is now a chance to rething the standard arduino layout.Manufacturers make less and less DIP processors available and even when they have them in their catalogue the delivey times are very very long. on the other hand some very exciting parts are available only in 3.3v (or less)

I think if we ever produce a 3.3v Arduino board we would have to change the layout so that people understand that things are different and the current shields (wired for 5v) can't be fitted.

it's a longer discussion but there is an opportunity for innovation there, always keeping things very simple

Basically I read this from your board layout. You have a lot of spare place and do not provide the wholes. Notice that I did not request that a second row is in place. Only the holes for the second row.

Your reply confirms my point. You want to take care of other stuff.

Basically it implies that I will not buy Arduino but Boarduino instead. Not a big deal because most people will stick to Arduino. The more anyoing part is that it also implies that Arduino Shields never fit a breadboard.

With regard to the 8u2 pins: I do not need the pins. I need the holes. I understand the point to not place lots of pins their. But I would expect an open source platform to be easily hackable. Thus I would greatly appreciate if the 8u2 pins would end at some holes where they could be soldered.

With regard to the feasibility of such a migration of course this is your judgement vs. mine. Since you are obviously successful in your market you must be at least somewhat right.But once you move to 3.3V these arguments will break down. At this time we will then see if you finally will fix it. I hope so, because it would make breadboarding much more confortable.

Deep_C

I always thought it was a ploy to make people have to buy their proto shields which are significantly more expensive than a basic board you can buy at radio shack. perhaps I'm too much of a conspiracy theorist though.

It sucks trying to bend the header pins, I tought about filling the holes with JB weld and drilling new holes, you'd have to grind off the pads and run wires to the next row. All that said, it would be a pain, and the money you'd save probably wouldn't be worth your time and effort.

further proof it's a giant conspiracy among those who have the means to manufacture the PCBs - they price it just enough that building your own isn't cost effective.

I always thought it was a ploy to make people have to buy their proto shields which are significantly more expensive than a basic board you can buy at radio shack. perhaps I'm too much of a conspiracy theorist though.

No need for conspiracy - it was really an "11th-hour" screw-up; they were rushing to get the original (ATMega8) boards done at the very last minute to get the lowest pricing (and to get them done on time, I suppose), board designs were being altered left and right, and one of the main guys shifted one of the headers a bit and didn't realize it. It was originally supposed to be "standard"; must've been a real surprise when they got the boards back from the PCB place. I don't think there is any conspiracy here, just another example of what can happen when you don't take the time to do things right, even if it means missing a particular deadline (at least in this case, no lives were at stake).

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It sucks trying to bend the header pins, I tought about filling the holes with JB weld and drilling new holes, you'd have to grind off the pads and run wires to the next row. All that said, it would be a pain, and the money you'd save probably wouldn't be worth your time and effort.

There are places out there that sell pre-bent header pins for this problem...

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further proof it's a giant conspiracy among those who have the means to manufacture the PCBs - they price it just enough that building your own isn't cost effective.

Really, the prototype PCB shields (if you get the bare PCBs) aren't that expensive. Only when you start buying a complete "kit" (with all the headers, reset switches, etc) does the price start going up.

My biggest gripe, though, with having to use a custom-made PCB for a shield is the fact that I have to order online for the parts; I can't just run down, and buy it someplace locally (like I can for a regular prototyping PCB).

For myself, though, it isn't really that big of a deal - if you are making a prototype, you might as well just integrate the ATMega onto the board as a "standalone" Ardunio, and build the rest of the circuit nearby; use a regular Arduino for design and testing, then incorporate a separate programmed ATMega microcontroller into the final prototype...

I will not respond to Arduino help PM's from random forum users; if you have such a question, start a new topic thread.

Actually by now I order custom boards and have them assembled and soldered. Since I learned how to deal wih Eagle a new world opened up. Still the non standard Arduino layout implies that I can not just plug some shield into a bread board. This is in the end what I am complaining about. The Arduino itself is not the issue. I can always buy a boarduino.

However I wonder why the shield makers do not come up with a solution. If the shields would start to offer a secondary set of holes, such that they could be resoldered to fit a bread board they should extend their market by some percent. If they also could agree on a standard layout then this could create the required push. Unfortunately standardization is slow and tedious. So my hope in this direction is close to 0.